An obligate parasite, or holoparasite, is a parasitic organism that cannot complete its life-cycle without exploiting a suitable host.
Part of the Andes mountain range, Aconcagua is the second highest of the Seven Summits, behind only Mount Everest in Asia. At 22,837 feet (6,961 meters), not only is it the highest mountain in South America, it is the tallest peak in all of the Americas as well as the Southern and Western Hemispheres.
Mt Whitney - in the California Sierra Nevada is the highest peak in the continental United States. Reaching an elevation of 14,508 feet, it towers more than 10,000 vertical feet above the Owens Valley, and because of it's lofty position, it is the most sought after peak in all of North America.